Apparatus for testing multiple-welded pipe



March 24, 1931. H. D. SCOTT 1,797,882

APPARATUS FOR TESTING MULTIPLE WELDED PIPE Filed July 27, 1928 2 Sheets-$11991. l

WITNESSES INVENTOR MM M a M March 24, 1931. D SCOTT APPARATUS FOR TESTING MULTIPLE WELDED PIPE INVENTOR 2 Sheets-Sheet Fil ed Jul Patented Mar. 24, 1931 UNITED {STATES mum I. so n, or WHEELING, wssw e liee #fifillflfl seem" CORPORATION, OF WHEELl G Wisvmsmm, A .OOREORATIQN w J .13): L1" f1 ,AJEPABATW R ew-es tvnwtetsrwanesn .l P

Theinvention relates to the testing for strength of weld joints between lengths of mult ple Welded pipe.

In laying some types oi pipe line, such as :t for natural gas and the like, the joints between, lengths of pipe are often made by Welding. Such joints can be mademore cheaply at the mill than in the field, and in order to reduce the cost of the pipe lines it is 10 now common practice to Weld two lengths of pipe in the pipe mills, which reduces by onehalfthe'iveld s necessaryin the fields. Such multiple welded pipe, however, are subject to itoughtreatment-in handling and in transpor- 15 tation, and many joints Which would he satisfactory if made When the pipes are Joeing laid, aredaniaged so as t o render the pipes unfit for use Without 're-Wel ding. It is thus important to testthe welded pipe before leaving .themill, to make certain that the Weld joints'are soundandstrong. l

"lesting of this multiple Welded pipe by dropping itthi'ough suitable distance 'is'not satisfactory, partly because this isin efiect a ransverse bend test in which only the opposed elements of the joint normal to; the direction of irn'pact receive ,the maximum stress and if a joint is defectiveat other points, the lower -stresses created-thereat may not sufiice to reveal the fact that the joint-is faulty. Furthermore, thepipemay he dented or othei wise 1 damaged, and there is danger to theavorkmen. 'l histy pe of test ,also interrl e 'es with and slows up the uniform and n e h pages o th ma i n a null} An object ofthe'invention is to providea rap ie ci ntsn safe me od. and: apparatus ior testing eld jo nts between lengths gotinultiple Welded pipe, which satisfactorovercomes the disadvantages ofthesliock or impact method referred to.

' Other objects are to provide'a method of and apparatusffor testing such o nts wh ch niak es use of the principle of reaction momerits of a transversely loaded beam', and

which is applicable to pipes of ,varymg .lengthsand diameter, which subjects eachele-V nnt of th j n to a q a e Q ifigQ 'EIQ- Q V. which can be performed 1n cont nuous 5U a i I. 1

fashion without mater ally increas ng manuises. ei-ia1 no. 295,738.

facturing costs, and vithout injury to the pipe. 2

In the accompanying drawings there is shown an apparatus which may be used in thepi acticeioi' the invention. Fig. lisa plan vies; of the? apparatus; Fig. 2' an elevation of the-right hand end olfithe' apparatus shown in-Fig.: ;1;'and1?ig. 3 aside elevation pantly If}; 'seition taken .on the-bIiQken line-1111+ILI, =1g.=.: f- Acordingtothe invention the eld joint between lengths of multiple elded pipe v is subjected to transverse bending stresses acting in one direction, andthe pipe is simultaneously rotated: topnogressiyely subj est the entire joint to bothtensionandcompression. -..l?l1eltransverseloadinginayibe, and pretenably is, accomplished by so supporting the pipe that all'or a portion ofit acts as a simple .heain, its Weight. creating bending moments 'Whose maximum effect is exertedat, or substantially at, the eld joint. In thepreferred embodiment, cantilever supporting is employed, that isthe pipe is supported from on'e end up to a joint adj acent a Weld jf iHV' and the succeeding length is unsupported, although if desiredthe iiieldedpipe maybe supported at its ends.

Various means maybe employed for supporting the pipe, such as axta'ble' or spaced tracks or guides. It is preferred touse a structure which initially supports the pipe I Y i a I along its fulllength, and whichhas a portion in uihich the suppoizts are interrupted in such niannei' than an appropriate length of the V Will hefunsupported, .Where one portion "9 the pin i lii ile f d-e m i in r cpixlaixcekyvith thep reffiegreplipractice,suitallole m ans r p pvid ite ntevei t h eliii dirfr sp nse fr m se siilg'th Pine. t t p abou $1 @ntiEY fi PPM a a fulcrum, Th nte rupts-. spawn P fi mbl i isl e l sh so that in passing loa er it afpipe ysrilljtui'ii ,tlnrongh ,at .leastone complete reyo lution. -Lil ewise, thepipe may be rotated, in ,i 'arious ways, and, with a structure such as that iferredto, anyilsuitable meansniay be employed to .roll the pipe overqit. Eor simplicity orconstruction' and operation, howeyer,

der maximum compression stress.

,' form a pipe support which is interrupted intermediate of its end portions, as shown in Fig. 1. All of these rails are mounted in an inclined plane, as shown'in Fig. 2, to provide a trackway which initially supports the full length of a multiple welded pipe made up of lengths 3 and 4 welded at 5;

The pipe is positioned on the trackway to have one section, 3 for example, supported during its entire travel, one track being adj acent the weld oint, as seen in Fig. 1. The pipe rolls by gravity down the trackway, and when it reaches the interrupted portion, length 4 is no longer supported by the tracks, but is supported as a cantilever beam adjacentto the weld'joint. The unbalanced force which tends to tip the pipe about the jointsupporting track as a fulcrum is overcome by providing means to hold the supported section on its supporting tracks. This is preferably accomplished by the use of a plurality of rollers 6 mounted in a framework 7, over the righthand track 1, 'Fig. 1. The roller mounting is vertically adjustable to vary the distance between the track and rollers, in order to accommodate pipes of different diameter, and is made long enough tosupport the pipe during its travel over the interrupted portion of the trackway. This roller backing holds the length 3 on the tracks when the pipe passes over the interrupted portion and the weight of length 4 sets up downwardly acting bending moments which create maximum stress in the weld joint.

At any instant when the weight of length 4 acts on weld joint 5, the upper portion of the joint is under a maximum tensile stress, and the diametrically opposed element is un- As the pipe rotates, each element of its weld point is thus progressively subjected to maximum tensile and compression stress,and by rotating-the pipe through a complete revolution,

every element of the weld joint is thus stressed. By making the Width of the interrupted portion such that the largest diameter pipe makes at least one complete'revolution in passing over it, provision is made for test ing pipes of all diameters.

hen the pipes tested are of uniform lengths, the tracks adjacent the weld may be inafixed position. The lengths, however,

- may vary, so that the weld joint in diflerent pipes, or runs of pipe, will be variously positioned. In order to provide for such a contingency, there is provided a movable track in the interrupted portions of one or more tracks 2. As shown in Figs. 1 and 3, track sections 8 are mounted on a carriage 9 movable on rails in alignment with the interrupted portion, the carriage being shifted. as re quired to move track 8 to support the pipe adj acent the joint in the manner described. An abutment 10 may be provided at the loading side of the apparatus, against which the ends of pipes are placed to properly align them for their travel downwardly over the trackway. Vvhen rotation has carried the pipe beyond the interrupted portion, it is again wholly supported along its full length, and may discharged by gravity upon any suitable receiving apparatus.

If desired, the joints may be further stressed by applying downward pressure to them. This may be done bya pneumatic hammerll adjustable longitudinally of the pipe length 4, the hammer being carried in a frame 12. As a pipe passes over the interrupted portion of the track, hammer 11 is operated to strike length 4 with downward blows, preferably at points adjacent its extended end, injury to the pipe being prevented in Various ways, as by regulating the impact, making the face of the hammer large and of the contour of the pipe, facing it with wood, etc.

The testing apparatus may be situated at any desired point in the passage of the pipe through a mill, and by delivering the pipe consecutively to the apparatus, the process becomes continuous, and does not materially slow down or interfere with progress through a mill. Also, the pipes may be inspected while being tested in this manner, so that in effect these two steps are combined into one. I

The invention provides a rapid, eilicient and economical testing of weld joints between lengths of multiple welded pipe, in which each element of the joint is subjected to proper maximum tensile and compression stress. Defects in the joints may be detected, the process may be made continuous, does not interfere with normal mill operation, is free from the disadvantages and danger of mpact testing, and the pipes are not inured.

According to the provisions of the pat ent statutes, I have explained the principle and mode of operation of my invention and have illustrated and described what I now consider to represent its best embodiment. Hpwever, I desire to have it understood that, within the scope of the appended claims the invention may be practiced otherwise than as specifically shown and described.

I claim:

1. An apparatus for testing the joints of multiple girt welded pipe, comprising means for supporting a multiple girt welded pipe as a simple beam with its joint subjected to ing beyond the support as a cantilever beam to set up bending stresses in a girt joint between said lengths, said pipe being laterally rotatable on said supports, and means associated with said supporting means for applying a load to said unsupported length while the pipe is being rotated to progressively subject said weld to both tension and compression stresses.

In testimony whereof, I sign my name.

HENRY D. SCOTT. 

